Cheap imported "rainproof" power supply (long version).
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- เผยแพร่เมื่อ 17 ธ.ค. 2024
- This is the long version of the video. A shorter version with less detail on the circuitry is also available. It starts the same so you can skip the first bit if desired.
• Cheap imported "rainpr...
I had high hopes for this power supply, since the images did show at least some effort to shed water over the outside of the case, but the implication that this could be mounted to a wall to power 12V equipment is not really accurate.
I could see this type of unit being used inside a box sign for 12V LED based signage where the unit was not directly exposed to the weather but had some protection from dripping water.
Things to note about cheap power supplies imported directly from China. They may not have good isolation between the mains voltage side and low voltage side so the 12V side should be regarded as being potentially at mains voltage. Made worse by the fact that some RCDs/GFIs can be rectified and smoothed power. Their rating is often pushing the limits, so always under run them. They have little or no interference suppression for RF noise. They don't always have adequate shielding of live mains connections and may pose a shock hazard.
If you require a low voltage supply for an application involving commercial use or a situation where people will come into direct electrical contact with the low voltage side then only use a power supply bought from a high profile electronic component supplier in your country. That removes a lot of liability and gives greater reliability.
If you enjoy these videos you can help support the channel with a dollar for coffee, cookies and random gadgets for disassembly at:-
www.bigclive.co...
This also keeps the channel independent of TH-cam's advertising algorithms allowing it to be a bit more dangerous and naughty.
A few minutes up and the long version has double the views. We watch you for the good long videos.
This is not the side of youtube where quick little videos are mainstays.
Keep in mind most of those views will be patron early access, so might have over representation of long viewers.
Thomas Murphy - How am I supposed to watch long videos in my 20 minute meal break?
@@Mark1024MAK Get fat, eat twice.
John Jones But he has to get back to work after 20 minutes. He already eats less to watch the short version at all.
I actualy got recommanded this version. I am not mad at all about it still haha :)
The snubber across the output rectifier is to supress "snap-off noise" When they are reverse biassed all diodes conduct in the reverse direction for a short time while the stored charge is cleared out. When the charge runs out the current stops very suddenly which if not supplied with an alternate path would generate a super high frequency noise spike. The snubber absorbs the spike and allows the current to stop more gently.
Big Clive can take the cover off, He's a professional. Thanks for the circuit breakdown. I always learn so much. While I know what the components do, sometimes it's hard to tell what they actually do in the circuit. I love the reverse engineering.
Retired Navy Nuke Electrician and retired Tampa Electric IGCC Process Specialist here. You're awesome. Nuff Said.
more like 50 watts max clive, I bought one of these and it lasted only about 90 minutes before the FET blew. Was using it to power a 50 watt cob LED. (48.7watts actual load)
Always the long version. Ill watch the short version but always the long version.
i watch both versions
That's what she said
just wondering how you watched this video 6 days ago when it was just uploaded??? hmmm time travel??? lol
@@adamayers1469 A theory: Eventually, with enough people asking, and asking, and asking, AND asking, some of the *non-Patreons* will see this question answered again, and again, and again, AND again, and *they* might realize if *they* made the *smallest* of contributions, *they* would no longer wonder how *some* people get here first... Again, just a theory in a ridiculously long run-on sentence. Maybe...
@@mikecowen6507 Wow you could have just said that your a patreon and you see the video before the rest of us you didnt need to be a smart ass, but thank you anyway now i understand.
As someone who routinely retrofits neon channel signs to LED, I can say with authority that I would not trust this power supply even in an enclosed sign. I'll stick with the type that are fully potted, they work a charm. I haven't had one fail yet in 5 years of harsh desert environment, including extremes from 120°F (48°C) heat, to full-on monsoon downpours, to zero-visibility dust storms.
Meanwell ftw.
When you measured the NTC I was waiting for you to probe the paper xD i was surprised when you actually pulled out the component! DERP
Yeah his prints always look damn good.
Yep i was thinking the same thing lol
Clive when we are on the priter topic, what printer and paper are you using?
@@Hagis2k There was a video on this, I recall. I can't seem to find it though.
After a few minutes of watching I also always forget that it's a print. Completely ignoring that there are SMD resistors half the size of a finger tip and always being astonished for a second how easy it is for Clive to write something "onto" a component...
I am sorry, I do not have the impatience to watch the other version.
Cute! :)
Thumbs up for the great clarity of the circuit diagramming (as usual) as well as the nice touch of the yellow paper, enhancing the ease-of-view. Much appreciated.
A non-slip matt may help with the photos sliding around on you. (Not complaining, just trying to help)
Its a 12vdc power supply and bug zapper built in to one unit.
I've found a simple but proven effective solution to greatly extending the life of these types of cheap chinese electronics devices.
Take them apart and conformal coat the circuit boards and all exposed wiring end connections with several layers of clear coat spray paint. Simple to do and substantially extends the harsh environment service life for it!
I come to the comments to learn tips like this in places like bigclive, AvE, ToT, etc
Yep. That's works really well. I did this on a digital wireless thermometer sender, except I used white appliance spray paint, 5 years and still going strong.
@@tonezoneuk If you're going to use appliance paint, get microwave oven paint. Youll be sure to have no conductive chemistry in the dried paint. Not always guaranteed for painting basic sheet metal appliances.
Will the paint crack if ya move or bend a wire. Years ago back in my youth i wanted to custom paint my dash, the dash of my vehicle was flexible, so i had to buy some additive to make the paint flexable, a friend of mine knew a paint dude who gave us the mix rates and tips. 10 years later it never cracked but was pliable. On my automotive splices expossed to the elements i will use the butt connector that are also heatshrink, after that i use liquid tape and just apply twice a years. I.E. trailer connections on my boat and other connections. Works great for me.
@@raymondmucklow3793 It might. If you want flexibility, stick with urethane conformal coatings.
Funny, I pretty much never understand what Clive says, with the only understanding of electronics being, just plug it in and hope it works, but I actually watch the longer versions of his videos because they are just that entertaining.
I keep expecting him to use the probes on the photographs.
speaking of voltage jumping I had a 12v motorcycle battery jump between the terminals of the starter solenoid while cranking, and this was arcing through 2 layers of duct tape and the factory rubber terminal boot on both connections. I noticed the plastic divider had broken off and in the process of tightening one terminal connection had been tweaked closer to the other.
To translate Chinese ratings into UK/US/Can/Aus ones, divide by the square root of Pi, then add 6.
I thought you just take the square root....and that's it?
Also that method *increases* percieved capacit for low values. Taking square root or 25%, whichever is greater, is my method.
The square root of Magnum?
This was great! I always look forward to these kind of explanations in your videos, keep them coming.
Long versions are the best, as you analyse yet another 'C E' deathtrap. Thanks Clive
It's odd what's implied by "outdoor". In Tenerife, things (electrical) obviously live outdoors 24x7x365 without any consequence. I've seen domestic sockets in the outside walls of buildings powering signs and vending machines ... and some have been there for years. I've also been there when it rained something like 10" in half an hour (slight exaggeration). The wind caused more damage than the rain, the local shops just poppped the outdoor fuse and then gave it half an hour to dry when the rain stopped before replacing the fuse and it was business as usual. It's the same the middle east and a fair few other areas ... when it's 40c most of the time no one makes any effort to waterproof anything, it only rains once a decade. Like BC says - it won't last half an hour "here" (his "here" and my "here" sound very similar and equally hostile).
But in the other sort of "here" where its hot and dry almost all the time it's just a bit of a bugger when they design and manufacture outdoor electrical goods and try to sell them in our here.
In a warm country like Tenerife you only have to worry about water getting into something from above, so you put an awning over it or seal any gaps around the top of it, this is why monsoon countries don't have a million electrocutions every year, you just throw some tarpaulin over an appliance. In colder countries however you have the extra threat of condensation, whereby water can enter a device from any angle since air creeps through any crack and then moisture forms on the first cold thing that air touches. As Clive mentions at the end of the video Britain is prone to Haar, which is sea fog and it gets inside anything that isn't fully sealed and gradually fills the thing up with water until it shorts out and pops.
This power supply would likely do what it says if it was used in Vietnam, but in Scotland it'd just get someone electrocuted on their lawn.
2:34 Completely agree... I've always when it comes to eBay chinese power supplies, generally buy one with intention to use about 30% of rating... So if I was going to need a 100W supply, I would look for a 300W supply. I know it is probably completely unnecessary... however I don't want to take a chance especially with unsupervised projects/devices.
Clive, glad to see another video. I have had palpitations since the last one. Thank you for your videos, please keep them coming. 🙂 cheers
Even if it's entirely sealed, it cannot truly operate for long outside in the elements unless it's constantly running. This is because if it isn't running, it will get very cold of a night time, then when the morning comes and the air gets warmer, the cold thermal mass of the power supply will attract moisture, this moisture will not only form on it's outside, but even on the inside of the unit as well.This water will then rust components.
I know this from experience, the only way for something to exist in an outside environment is if it's kept warm, usually by running the power supply it will be warm, then it will not create any condensation, because condensation is from warm air hitting a cold surface, not from cold air hitting a warm surface. Thus it will be safe as long as it's running.
As you pointed out, it also shouldn't have a single hole even the size of a pin leading into the main circuit area, because little ants and spiders will get into it and destroy it by being shocked and exploding their guts all into it. Therefore the unit has to be entirely sealed. Once it's fully sealed, and kept warm by operating, then it truly will run without any problems and will last a long time outside.
Long version hyper details all the way. Thanks for the enlightenment.
Regards Tony Henderson
I watched both videos and i'm not disappointed.
i had an advertised water proof power supply for a camera, was fine until we had some sideways snow and freezing temps, brought it inside after it stopped and after a while water poured out, if they'd have left the hole for the led out, it'd have been fine, i also bought a 12v 5a supply, thankfully it was damaged in shipping, what i found inside was scary, old reclaimed power supply recased, old leads cut with what was left nearly shorting, a shake or a jar could have easily made them touch, no fusing either.
Hmm. Top cap is no better than the bottom one. Half of the top cap screws have the thread in "outer volume", but other half - in the inner volume, providing a path for water to leak inside. (Although it's more of extrusion issue.) Oh, and extrusion itself is consist of two parts...
Thx, in your Videos you gave me the understanding of switching mode power supplies, now it's much easier for me to fix them.
Hi Clive - I think it would be really interesting if you could make another short video where get your scope out and probe the waveform / frequency of the switching circuit - and especially to see how the feedback circuit operates under varying loads? Please?
I work for a sign manufacturing company. All of our signs are grounded and the insides are shielded from rain and we still use ip67 rated power supplies for the LEDs. Not totally necessary but they do seem to have longer lives. The message centers that we order do not have sealed potted power supplies though and they seem to last pretty well, but those cans are a bit better sealed than you average sign.
i never have any clue in the slightest what this electrical wizardry means but i enjoy your videos none the less.. =]
I think that you don't need long/short versions of your videos. People who don't want to watch some part can easily jump over it.
Petri Lopia, and I think you should keep your opinion to your self. I am one of those that has HDD and a lot of time won't watch a long video .. having long/short versions insures Clive gets more views.
Water-resistant? With the screws holding the shroud on placed like that? Each one in a well that allows water to build up and leak past the threads.
But maybe that's deliberate to wash the spiders out.
bdf2718 Hahaha you made me laughed out.
Another excellent video BigClive as always. And for that price not a bad enclosure for projects. Providing us with quality entertainment thanks
Good Video Clive, always the long ones for me. Seeing the different manufacturing designs is interesting.
The reason for the diode inside the MOSFET transistor: the device still has diode junctions that make up the FET, the extra diode prevents reverse bias on them which can cause junction latch-up.
@02:28 no (rubber) seal, 💦 water will penetrate the top, capial effect pull the moisture in at the screws. Screwholes are convenient cups...
@14:50 Default the set “mosfet/duo-diode” is not connected throw the case, but is something died,... it easy could!
Excellent it the rain does not get it the insects will, bang goes the power supply! Excellent and the bonus, it might be live when you touch it.
The issue with transformer frequency is the iron core. At low frequencies, you build up larger magnetic fields in the core and saturate it faster. Once the core saturates, it is no longer able to concentrate the magnetic field.
Another way to think about transformers is that there is only just so much energy in a single pulse or cycle (because more *would* saturate), so the more pulses you have, the more energy can go across. More pulses = high-frequency. More energy in the same time = higher power rating.
Got a little 10W led driver from ebay recently, the whole thing is potted inside an aluminium extrusion. The ad had 10-100W models. Didn't mention water or rainproof, but I'm sure it's better at it than this.
Edit: haha just heard your potted comment
Just there on the outside stamped on the aluminum "to be used in arizona desert" only.
desert still has insects I presume :)
@@maicod Especially the kind with hooked tails and stingers. 🦂
@@maicod no moisture.
the insect's bodies contain moisture enough :D
@@maicod touche sir. I was trying to be funny, perhaps i should have said the Sahara, mercury or the moon.
The metal tab on the back of a MOSFET is electrically connected to one of the pins, no? The drain pin, I think. Maybe that's only true for some variants. In any case it looks unsafe to clamp that to the case. Also, I'm reasonably sure that insects shorting out high voltage electronics was the original meaning of the word bug that is now used to refer to software malfunctions.
Was a moth stuck in a relay of the Harvard Mark II computer. It was extracted and sellotaped inside the computer's log book.
americanhistory.si.edu/collections/search/object/nmah_334663
ManWithBeard1990 - It looks like the transistor and output diode are using fully insulated plastic packages.
ManWithBeard1990 - most spiders, ants and flying insects are not very conducive when alive and dry. The problem is when a slug or snail gets in, or there is a build up of dead insects and dirt. Moisture then makes the mess conducive.
ManWithBeard1990 - In computing, bug comes from insects getting trapped in the mechanism, not insects causing short circuits. The early computers were electro-mechanical systems using telephone relay sets and uniselectors. These typically operated on 50V DC supplies. Later, faster computers used valves (tubes). These used higher voltages.
@@RenThraysk - Edison gets 1878 credit here, to my mild surprise: interestingengineering.com/the-origin-of-the-term-computer-bug
But also -- even though I've seen Harvard's bug -- I'da sworn it was from the Mark I; nope :-)
Excellent diagnosis and tutorial, though it does need a British Wellington boot to increase the IP rating.
Ref Chinese " CE" marking abbreviation, what about "Chance Enhanced".
Love the high quality photographs, and schematic.
Thanks for sharing and best regards from the Black Country.
A proper set of Wera screwdrivers, very nice. Wera and Wiha are the only manufacturers I buy screwdrivers from.
"It's always quite interesting looking at other people's electrical work." - just as long as you don't get BLAMED for other people's electrical work.
Always take pictures beforehand.
I got that same set of screwdrivers for Christmas. They're awesome, especially compared to my previous assortment of five screwdrivers that are always the wrong size.
Do not open the cover, or you may expose yourself to cheap components and potentially dangerous circuitry.
But that's exactly what we love on this channel :)
@@AwesomeMcTasty Indeed it is!
The dangerous it is the more entertaining it is
I just realized it's been a while since you've meggered anything. When you mentioned the inconsistent quality of the transformers in these things, my first thought was "test the isolation."
Actually when I saw that there is a long and a short version, I thought that he took the transformer apart. Now that Ive seen it, Im wondering what there is you could cut out :D
I could see it hanging in an open barn, shed or other outbuilding where it's shielded against the worst of the weather as well as a sign as Clive suggested.
IF anything it's a nice project box.
Now I'm curious about the epic insect nuclear reaction, but when you do it, please don't hurt any living BEEing
Rain will shed over top but catch in the bottom lip and along the sides. PS I at least plug things in and test to see if they work.
Would you be able to modify any of these to make them safer and less noisy? Or would it need a whole new PCB?
22:16 ...err is that a friction fit...as in a friction fit for a loose dangly piece of metal electrically connected to the ungrounded case hovering millimetres away from the legs of a MOSFET at 340v to ground (240v peak)....?
Would seem inadvisable to use this somewhere there was any vibration at least...
Good to see your arms are still working.
Love my wera screwdrivers best thing I've ever brought tried whia but they were crap! Great video clive
Would love to see a full power and overload test to see what temperatures are like
OK this is weird, I've just bought an uncased power supply - 9V 5A to go internally in my Spectrum +2
@bigclivedotcom - Side question; How do you store your USB devices (Not plain old thumb drives but those larger devices like the meters, USB Test Load, and so on?) Thinking on a better way here, maybe a "fishing lure" box - But you may have a different & better idea so I'll ask - Thanks!
In a huge pile of technical clutter on my bench.
@@bigclivedotcom Aah, thank you. I'll keep looking for something that'll work here. Clutter sure happens, doesn't it?!
@@mrsheesh3743 Clutter is normal at an active bench.
If you flip the track-side photo rather then that top-side, we can read the text on the components. Of course, then the print on the track side will be hard to read.
"Let's just whip everything off" Ok big boy lol. :-D
My guess on the solder pads on the fuse track on mains input is to possibly fit a fuse fail neon. ?
I didn't even entertain the idea of clicking the short version first although I will watch it.
Those solder blobs on the Neutral terminal look like an attempt at a spark gap; normally seen between live/neutral and earth to allow high voltage surges to jump to earth... Anyone agree? Also think that and the 'fuse' should have been the on Live terminal but as they don't care about Earthing it's not a surprise the terminals are reversed...
Can't really be a spark gap as there's a fuse bridging the two pads. The spark gaps tend to be across areas where a high voltage could occur.
They should add something to limit inrush current on all laptop power bricks. I hate it when they spark when you plug one in an AC outlet and it can't be a good thing over long term..
Some do have inrush limiters, but there's still a significant inrush.
I've seen this type of feedback before, I was of the understanding that because the cathode of the feed back LED is at a fixed voltage due to the reference diode under it. When the output voltage starts to raise the LED gets brighter and this is fed back to the Photo transistor which turns on a little more thus lowering the voltage at pin 2 of the IC. The IC sees this drop and decreases the Mark Space ratio of the pulse to the transformer (Larger Space) this then lowers the output voltage. The opposite happening if the output voltage drops.
This is similar to Buck Boost converters..
Correct me if I'm wrong.
I think the opto isolator is switching the primary side off completely.
I think the tree with the dubious wiring is in JW’s garden.
I love watching these videos!
You'd think the extra was to possible bridge if the tracks blew, but, they are all still connected, it looks more like an anchor point
Not running at 50Hz mains is not to save weight (though it does) it's to save energy. Switching at varying pulse width depending on load is what makes an SMPS more efficient than a linear voltage regulator like a 5A 7812 chip. Doing the switching on the mains side avoids the losses of having two power conversion circuits (first a transformer, then an SMPS coil). Now I'm not saying this craptastic model is efficient, as a matter of quality.
Do you think the bigger cases just use a different mosfet? The bigger cases make you think you are getting something more beefy?
The diode at the gate of the MOSFET is to decrease turn off time.
I don't think the difference between "waterproof" and "water resistant" translates well. Or they just don't understand the concept. I bought a nice, cheap little handlebar mount radio that was supposed to be waterproof a few years ago and was very happy with it on my bike for a few months but the bike sat outside in the parking lot while I was at work every day and after a while the radio's buttons started acting up. When it finally died I opened it up and found water lines halfway up the inside of the housing.
Another time I bought a "waterproof" handlebar mounted clock but the first time it rained water was visible inside it. The part that attached to the handlebar was basically a metal cup with no drain hole and when I opened up the clock part (basically a watch movement in a housing) it had absolutely no seal of any kind to keep the water out. I drilled a drain hole in the cup and covered the openings in the watch with silicone sealant and it still works several years later but it is a royal pain every time the clocks change or the battery dies.
The pads around the Active terminal appear to be for spark control
10:55 - the sense resistors (R7 - R10, 0.3 ohm) - aren't they connected to pin 4 via R6?
Yes. There's a resistor between them and the chip.
what brand are those modular screwdrivers your using? looks very convinent
Wera.
And they're Wera expensive. tinyurl.com/y5lb36hz
@@petehiggins33 Although, that's a hella belt pouch :-)
another well explained video mr clive. i don't understand why they would put a LED inside of something that you won't be able to see. what's it's purpose clive?
Probably because it's a generic module. They might also use the same board design in different products.
Those solderpads on the neutral could be a sparkgap perhaps?
What brand and model is that ESD safe screwdriver set? I think I'd like to own one. Seems thick enough to not wear your hands out, the rubber parts ensure a great grip and that plastic seems extremely tough (I've seen you use them to pry things and unscrew overtorqued screws - That's some great, non-conductive plastic!).
The red/yellow electrical screwdriver set is by Wera. It's a VDE rated set for live electrical work.
Interesting to see the ground of the primary DC side (at 350+ Voltish?) sneak under that 750K SMD resistor. What's the separation there? 0.5 mm??
Looks like there's enough room on the circuit board to use through hole resistors instead of those two groups of 4 resistors. Also, they probably could have made tiny boards with the controller and mount them vertically in order to get a completely through hole design.
Would you have felt better if they used some kind of adhesive kapton/whatever tape on the bottom and on the sides (except where the to-220 parts screw to case) ? Seems like that could be a cheap and easy way to improve things a bit.
Agree with you on the insects part through. Though with a fully through hole design maybe they could just spray some epoxy on the back or maybe have a thin layer of foam stuff you sometimes see in power supplies for sale in insect rich countries.
Not a fan of that big 33uF 400v capacitor so close to the bridge rectifier, it will cook itself over time. Seems like there's enough space to use a thinner and longer one laid down on the board, making more distance between the capacitor and the bridge rectifier and hot ntc. They could have rotated the bridge rectifier and screw it to the case (or a metal bar that also heatsinks the to-220 part) for some extra heat dissipation - at that 100w of output, the rectifier alone would dissipate around 1-1.5 watts.
i M CONCERNED ABOUT THE Line input PC trace adjacent to the aluminum case isolation through the "green" PC board coating. Time, vibration, moisture could eventually cause a "hot" case because it is not grounded to the ground line coming in. This could be lethal, especially in an outdoor (pool) environment. Better make sure there is a GFI for protection.
@bigclivedotcom what are the screwdrivers you used in the video? Those are exactly what I was looking for. Awesome video
Wera VDE for live electrical work.
@@bigclivedotcom oh wow thanks so much👍👍
Even the relatively large mosfet will fail the 1,5mm functional isolation requirment? And the product will fail excessive dust, plants and vermin, maybe corrosion, UV and more (60950-22).
Great break down of the circuit Clive
Not even a capacitor between primary and secondary... yikes! Add a few feet of wiring to the output and you've got yourself a pretty effective radio interference generator I bet!
And if that poor excuse for a power supply can handle 120W on more than a brief intermittent basis, I've got a bridge to sell.
It looks like a flyback type supply 13:44 , they are not usually used in excess of about 100W. Clive's description of how it works was not completely accurate. A flyback stores the energy in the core and dumps it to the output at the non-conducting state of the switching transistor - the high frequency alternating current does not pass through the transformer in the 'traditional' sense.
Was wondering if you go see your doctor after exposing yourself to electric shocks like the last video just to make sure everything is not cooked and your heart is running right? also i prefer the longer videos, keep them coming.
Bug schmug if it bridges something the electric will blow the fault clear...(and possibly the components on the board too)
I noticed there was a component missing from the board as assembled, but could not make out the marking to indicate what it was. Could you clarify that?
Filter capacitor at the input? More a token gesture nod to a filter capacitor since it should really be a larger X2 suppression cap.
I think if the price is right, you could wire the unit up with leads a bit longer than you need. Tip it upside down and then fill the unit with 2-part gella reenter-able potting compound and then once cured, install it. Could be a nice solution if modified a bit.
The polymer gel would probably cost more than the power supply.
Another fantastic informative video. Thanks Clive.
Is that tree at the restaurant across the road from the counting house at george square?
I think they might have been done by the same company.
I wish youtube offered an option to see a short or a long version of every video. So that ADHD millenials can give you all the views you need and i could enjoy my nice and long vids.
It does that with the skip facility. Every video has an "engagement" percentage that shows how much of it people actually watched. In this video it's currently standing at 46.5% which is pretty high for a typical video.
The "rainproofing" feature reminds me of the sky minidish LNB "rainproofing", where they have a token gesture pull-down shroud that does jack all for rainproofing the F-connectors resulting in the cables filling with water and flooding the receiver boxes... :P
Change the background board with some slight brighter colour for better visibility.
With this background you made sufficient videos
Looks as though there should be another section to cover the connections. As you say spiders get anywhere they can.
ARE THE SCREWS ON TOP NICE STEEL ONES LIKE THEY HAVE ON SOLAR LIGHTS THAT RUST AFTER ONE WEEK THEN BREAK THE PLASTIC AS THEY EXPLODE WITH RUST
LOL, Following the Chinesium Standards it would seem adding a extra " 0 " (Zero) on the end of the stated power rating is common a practice. When a particular item is rated at oh say 20A what they are in fact saying is it will only start smoking at 10A not burst into flames or explode until the rated 20A has been achieved. Knowing this as fact you just order things rated at two or three times the stated rating and it will do the job just fine. I order boat loads of electronic's modules and parts monthly. Using this logic I'm more then happy with they're products.
Haar is very familiar here in Fife. Do you get it in the Isle of Man or is it only an East Coast thing?
Parts of the island regularly get blanketed in sea fog.
Design and 3D print a new Bum for it as a video? :) I have done this for some similar supplies.
Liked cause " FULL BRIDGE RECTIFIER" electroboom quote